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With the use of a crossover study design, we investigated the respiratory and cardiovascular effects of naloxone administration in eight healthy Rocky Mountain wapiti (Cervus elaphus nelsoni) anesthetized with carfentanil (10 microg/kg... more
With the use of a crossover study design, we investigated the respiratory and cardiovascular effects of naloxone administration in eight healthy Rocky Mountain wapiti (Cervus elaphus nelsoni) anesthetized with carfentanil (10 microg/kg i.m.) and xylazine (0.1 mg/kg). Anesthetized animals showed profound hypoxemia with mild hypercapnia, tachycardia, hypertension, and acidosis prior to naloxone administration. After monitoring equipment was placed, animals were administered either naloxone (2 microg/microg carfentanil i.v.) or an equivalent volume of normal saline. Mean values for PaO2, PaCO2, heart rate, and respiratory rate were significantly different between naloxone- and saline-treated groups, but mean blood pressure, hematocrit, and serum electrolyte concentrations were not. Mean PaO2 was 23.0 +/- 4.1 mm Hg prior to administration of naloxone or saline and increased to 50.2 +/- 7.3 mm Hg after naloxone administration. Mean PaO2 of saline-treated animals did not change significantly. Electrocardiograms of three saline-treated animals suggested myocardial hypoxia. Hypoxemia appeared to be caused by respiratory depression, hemodynamic alterations, and lateral recumbency. All but one animal remained anesthetized after naloxone administration. Anesthesia in all animals was reversed in < or = 4 min with naltrexone (100 mg/mg carfentanil i.v. s.c.) and yohimbine (0.1 mg/kg i.v.). One bolus of naloxone improved oxygenation in carfentanil-xylazine-anesthetized wapiti.
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Madagascar does not have native wild felid species; however, distinct populations of free-ranging “forest cats” of unknown species are known throughout the island, including at Ankarafantsika National Park, Bezà Mahafaly Special Reserve,... more
Madagascar does not have native wild felid species; however, distinct populations of free-ranging “forest cats” of unknown species are known throughout the island, including at Ankarafantsika National Park, Bezà Mahafaly Special Reserve, Makira Natural Park and the Masoala peninsula. Malagasy “forest cats” are commonly considered invasive lemur predators and competitors with endemic carnivores as well as a nuisance exotic species that kill poultry. These cats may be descendants of African wildcats, European wildcats and/or domestic cats; however, no research on their genetic origin has been published. To determine their taxonomic status, genetic data from short tandem repeat markers was assessed for three wild-caught “forest cats” from the Bezà Mahafaly Special Reserve (BMSR) and 27 “forest cats” from Ankarafantsika National Park. Bayesian analyses comparing the Malagasy “forest cats” to approximately 1900 domestic and wildcat sub-species suggest the Malagasy cats are descendents of domestic cats from the Arabian Sea region, including the islands of Lamu and Pate, Dubai, Kuwait and Oman. Additional genetic influences may descend from India and Pakistan. Combined with cultural and historical information, these data suggest that these felid populations are likely descendents from cats that immigrated to the island on trade ships, particularly along early Arab trade routes.
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This study was conducted to evaluate whether the administration of naloxone (NAL) had an impact on the speed or quality of recovery in servals anesthetized with ketamine, butorphanol, and medetomidine. Twenty-two clinically healthy,... more
This study was conducted to evaluate whether the administration of naloxone (NAL) had an impact on the speed or quality of recovery in servals anesthetized with ketamine, butorphanol, and medetomidine. Twenty-two clinically healthy, captive servals (Leptailurus serval) were anesthetized for routine physical examinations using ketamine (3 mg/kg), medetomidine (0.03 mg/kg), and butorphanol (0.3 mg/kg). Eleven animals were administered atipamezole (5 mg/mg medetomidine) and NAL (0.1 mg/mg butorphanol), while the other 11 were administered atipamezole (5 mg/mg medetomidine) and sterile saline (SAL). There was no statistically significant difference in recovery time between the NAL and the SAL group; similarly, there were no significant differences between groups at any time point for the measures of quality of recovery used in this study. This investigation was unable to detect a clinically significant difference in anesthetic recovery for servals that received NAL relative to those that did not. These results suggest that butorphanol does not routinely need to be antagonized in captive servals that are anesthetized with these dosages of ketamine, medetomidine, and butorphanol. It may be more important to administer opioid antagonists in free-ranging animals, where residual sedation would be more detrimental. In these cases, a long-acting antagonist, such as naltrexone, may be indicated. An opioid antagonist, such as NAL or naltrexone, should always be available for emergency administration whenever opioids are used. Additionally, this study provided physiologic data for servals anesthetized with a ketamine-medetomidine-butorphanol combination.
Research Interests: Zoology, Carnivora, Medicine, Female, Animals, and 14 moreMale, Ketamine, Anesthesia, Sedation, Narcotics, Zoo, Veterinary Sciences, Opioid, Naltrexone, Naloxone, Butorphanol, Anesthetic, Medetomidine, and Zoo animals
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Four female Japanese macaques (Macaca fuscata) from the same group as well as Wolf's guenon (Cercopithecus wolfi) and a Western lowland gorilla (Gorilla gorilla gorilla) from a second institution presented with vaginal foreign bodies... more
Four female Japanese macaques (Macaca fuscata) from the same group as well as Wolf's guenon (Cercopithecus wolfi) and a Western lowland gorilla (Gorilla gorilla gorilla) from a second institution presented with vaginal foreign bodies in parallel with diseases of the urogenital tract or with endocrine disorders. These foreign bodies were associated with a mild to marked, diffuse vaginitis in all cases. Underlying pathological conditions consisted of a cavernous uterine hemangioma in a 20‐year‐old macaque, diffuse endometritis in a 21‐year‐old macaque, an in situ endometrial carcinoma in a 24‐year‐old macaque, endometritis and an ovarian cyst‐like structure in the 27‐year‐old Western lowland gorilla, chronic cystitis and chronic renal disease in a 24‐year‐old macaque, and a history of hypothyroidism with irregular reproductive cycles in the 12‐year‐old Wolf's guenon. Vaginal foreign bodies have been reported in nonhuman primates used in biomedical research, but their concurrence with underlying conditions has not been explored. In women, vaginal foreign bodies have been linked to serious underlying medical conditions. This case series emphasizes the recommendation to investigate this abnormal behavior for underlying medical or adverse psychosocial conditions in primates under human care.
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Jaguars are an endangered species and represent the only felid in the Americas from the genus Panthera. Wild jaguars continue to be threatened by habitat loss and other human impacts; therefore, maintaining a healthy breeding population... more
Jaguars are an endangered species and represent the only felid in the Americas from the genus Panthera. Wild jaguars continue to be threatened by habitat loss and other human impacts; therefore, maintaining a healthy breeding population in zoological institutions is critical to jaguar survival. Ovarian adenocarcinoma (OC) commonly occurs in adult jaguars housed in North American zoological institutions, and is an important cause of mortality in this population. This neoplasm is very rare in domestic cats and has not been reported in other zoo felids. Archived, formalin-fixed, paraffin embedded (FFPE) reproductive tissues from 55 female jaguars were examined. OC was confirmed histologically in 22 (40%) jaguars originating from 17 zoological institutions. Seven jaguars with OC were traced back to one breeding pair, and pedigree analysis shows an autosomal dominant pattern of inheritance. The purpose of this study is to investigate the genetic pathogenesis of ovarian adenocarcinoma in jaguars by identifying an inherited germline mutation in BRCA1, BRCA2 or other cancer genes with known involvement in human ovarian and breast cancer. A candidate gene approach was used for investigation, as minimal wild type gene sequences are available for the jaguar, and no previous studies have been undertaken to investigate genetic mechanisms of disease in this species. By utilizing genomic information available from closely related species, a targeted library preparation and next-generation sequencing approach was used to evaluate exon sequences of multiple cancer genes (n=276) in paired OC and normal FFPE tissues from each jaguar. Probes designed in this assay captured the majority of target regions, covering 92% of total base pairs within the 1.4 Mbp target region. Average depth across FFPE samples was 114x. Multiple variants were detected in jaguar candidate genes. One variant of interest in BRCA2 exon 11 includes a single nucleotide variant in the jaguar sequence that corresponds to position c.3732 in humans. The c.3732C>G variant gives rise to the substitution p.Ser1252Arg which is predicted to be potentially deleterious. This variant was present in all jaguar samples, but demonstrates loss of heterozygosity in the jaguar ovarian adenocarcinomas compared to paired normal tissues. This variant is in the region of exon 11 containing several amino acid (BRC) repeats essential for RAD51 binding. Maintaining genetic diversity in endangered animals, such as the jaguar, while preserving the species in zoological institutions by captive breeding is an important aspect of their conservation. Identifying a germline mutation associated with OC in jaguars will enable the identification of mutation carriers and will allow for educated breeding decisions, better disease monitoring, and earlier intervention. Jaguars may also be a naturally-occurring animal model that parallels hereditary breast and ovarian cancer syndrome in humans. Citation Format: Sarah Corner, DVM, MS, Dipl ACVP, Maciej Parys, DVM, PhD, Anneke Moresco, DVM, PhD, Vilma Yuzbasiyan-Gurkan, PhD, and Dalen Agnew, DVM, PhD, Dipl ACVP. OVARIAN ADENOCARCINOMA IN JAGUARS (PANTHERA ONCA): A NATURALLY-OCCURRING MODEL OF HUMAN INHERITED OVARIAN CANCER? [abstract]. In: Proceedings of the 11th Biennial Ovarian Cancer Research Symposium; Sep 12-13, 2016; Seattle, WA. Philadelphia (PA): AACR; Clin Cancer Res 2017;23(11 Suppl):Abstract nr TMEM-020.
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Abstract: In zoos, rock hyrax (Procavia capensis) are commonly maintained in groups and population control is necessary. Here we report on hydrometra prevalence in a group of rock hyraxes. Prevalence of hydrometra in this small group... more
Abstract: In zoos, rock hyrax (Procavia capensis) are commonly maintained in groups and population control is necessary. Here we report on hydrometra prevalence in a group of rock hyraxes. Prevalence of hydrometra in this small group (4/8) far exceeds reproductive pathology prevalence previously reported for this species under managed care. Affected females were nulliparous, but had not been contracepted; instead they were maintained as a single-sex group. The first case presented as sudden death and three additional cases were diagnosed antemortem via ultrasound. Two of these underwent ovariohysterectomy to treat the severe hydrometra. The last case was a mild hydrometra and during follow-up exam was found to have spontaneously resolved. Detailed information regarding clinical presentation, diagnostics and surgical techniques are provided.
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ABSTRACT Overpopulation of selected groups of animals is widely recognised as an issue that can have adverse effects on several current global problems, such as animal and human health, conservation and environmental changes. This review... more
ABSTRACT Overpopulation of selected groups of animals is widely recognised as an issue that can have adverse effects on several current global problems, such as animal and human health, conservation and environmental changes. This review will, therefore, focus on recent novel contraception together with future technologies that may provide additional contraceptive methods.
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Contraception is necessary to manage zoo animal populations and to be able to house animals in groups without producing additional unwanted offspring. In felids and canids, an association between exposure to progestins and the occurrence... more
Contraception is necessary to manage zoo animal populations and to be able to house animals in groups without producing additional unwanted offspring. In felids and canids, an association between exposure to progestins and the occurrence of endometrial and mammary gland pathology has been documented. Therefore, the Association of Zoos and Aquariums (AZA) Wildlife Contraceptive Center recommends the use of deslorelin acetate for long-term contraception in carnivores. Return to cyclicity after deslorelin treatment has been variable; some individuals show ovarian suppression for long periods after the expected end of the deslorelin efficacy. In an attempt to reduce the time to reversal, techniques to locate and remove previous implants are being developed. This report documents the successful implementation of high-frequency ultrasonography in lions (Panthera leo) to locate and direct surgical removal of multiple deslorelin implants placed at least 2 yr previously as well as the return of follicular activity in both females at 7 months post-removal of implants.
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A juvenile to young adult, male, great horned owl (Bubo virginianus,GHOW) was presented to the wildlife rehabilitation hospital at Lindsay Wildlife Museum (WRHLWM) due to trauma to the right patagium from barbed wire entanglement. On... more
A juvenile to young adult, male, great horned owl (Bubo virginianus,GHOW) was presented to the wildlife rehabilitation hospital at Lindsay Wildlife Museum (WRHLWM) due to trauma to the right patagium from barbed wire entanglement. On presentation, both corneas were irregular, dry, and no movement of the third eyelid was noted. A severe corneal enlargement/globoid appearance was the predominant ophthalmic feature. The fundus was normal in both eyes (OU). Over the course of several days, both corneas developed edema combined with further dessication at the ocular surface associated with diffuse dorsal fluorescein stain uptake. Repeated ophthalmic examinations found normal intraocular pressures and an inability to move the third eyelid over the enlarged corneas. The bird was deemed nonreleasable due to severe wing damage and poor prognosis associated with eye abnormalities and was humanely euthanized. Postmortem CT, enucleation, and histopathology were performed to evaluate the ocular anatomical abnormality and confirm the suspected diagnosis of keratoglobus. This GHOW represents the first reported case of presumptive keratoglobus in a raptor.
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One Health is a collaborative trans‐disciplinary approach to health; integrating human, animal, and environmental health. The focus is often on infection disease transmission and disease risk mitigation. However, One Health also includes... more
One Health is a collaborative trans‐disciplinary approach to health; integrating human, animal, and environmental health. The focus is often on infection disease transmission and disease risk mitigation. However, One Health also includes the multidisciplinary and comparative approach to disease investigation and health of humans, animals, and the environment. One key aspect of environmental/ecosystem health is conservation, the maintenance of healthy, actively reproducing wildlife populations. Reproduction and reproductive health are an integral part of the One Health approach: the comparative aspects of reproduction can inform conservation policies or breeding strategies (in situ and ex situ) in addition to physiology and disease. Differences in reproductive strategies affect the impact poaching and habitat disruption might have on a given population, as well as ex situ breeding programs and the management of zoo and sanctuary populations. Much is known about chimpanzees, macaques, and marmosets as these are common animal models, but there is much that remains unknown regarding reproduction in many other primates. Examining the similarities and differences between and within taxonomic groups allows reasonable extrapolation for decision‐making when there are knowledge gaps. For example: (1) knowing that a species has very low reproductive rates adds urgency to conservation policy for that region or species; (2) identifying species with short or absent lactation anestrus allows ex situ institutions to better plan contraception options for specific individuals or prepare for the immediate next pregnancy; (3) recognizing that progestin contraceptives are effective contraceptives, but may be associated with endometrial hyperplasia in some species (inLemuridaebut not great apes) better guides empirical contraceptive choice; (4) recognizing the variable endometriosis prevalence across taxa improves preventive medicine programs. A summary of anatomical variation, endocrinology, contraception, pathology, and diagnostics is provided to illustrate these features and aid in routine physical and postmortem examinations as well as primate management.
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Male associations are a typical component of elephant society, allowing bulls to practice appropriate social behavior. To improve zoo elephant welfare, it is important to provide bulls with social opportunities. In fall 2018, Denver Zoo... more
Male associations are a typical component of elephant society, allowing bulls to practice appropriate social behavior. To improve zoo elephant welfare, it is important to provide bulls with social opportunities. In fall 2018, Denver Zoo added two bull Asian elephants to its existing all-male group of three bulls, offering the opportunity to conduct a systematic behavioral study of the integration of the new bulls into the resident group. We recorded aggressive and affiliative behaviors before, during, and after the introduction of the new males. The proportion of aggressive behavior was significantly higher during the five-month introduction period compared to before their introduction. By the end of the study period, the elephants engaged in significantly more affiliative behavior and less aggressive behavior than during the introduction period, suggesting they had formed a new stable social dynamic. These results suggest group compatibility and positive elephant welfare resulting from housing male elephants together and can be used to inform management plans for bull elephants that prioritize their welfare.
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For over 25 years, the Reproductive Health Surveillance Program has collected, processed, evaluated, and archived reproductive tracts from nondomestic mammals submitted by zoos. The analysis of the data from this archive has been used to... more
For over 25 years, the Reproductive Health Surveillance Program has collected, processed, evaluated, and archived reproductive tracts from nondomestic mammals submitted by zoos. The analysis of the data from this archive has been used to recognize lesions associated with exposure to certain contraceptives; but arguably more importantly, to also document naturally occurring lesions. The goals of this program are to enhance the reproductive management of captive and free-ranging species by providing information about the effects of various contraceptives and to provide basic information regarding the natural reproductive histories and naturally occurring lesions in male and female zoo animals.
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In a collection of 6 young binturongs ( Arctictis binturong), 3 presented with anorexia, lethargy, and footpad swelling diagnosed by surgical biopsy as calcinosis circumscripta. Despite supportive care over the next 4 years, affected... more
In a collection of 6 young binturongs ( Arctictis binturong), 3 presented with anorexia, lethargy, and footpad swelling diagnosed by surgical biopsy as calcinosis circumscripta. Despite supportive care over the next 4 years, affected binturongs had progressive weight loss, hyperphosphatemia, and hyperkalemia and developed large radiodense deposits in tissues adjacent to appendicular joints, thoracolumbar vertebrae, and the sternum. Two binturongs died and necropsies showed severe periarticular mineral deposition with fibrosis and granulomatous inflammation. Additionally, binturongs had mineralization of distal renal tubules, mineralization of the renal interstitium, and marked mineralization of the pulmonary interstitium and peribronchiolar smooth muscle. Foot biopsies from the surviving binturong were evaluated by spectroscopic microanalysis and were positive for hydroxyapatite, Ca10(PO4)6(OH)2. Periarticular and footpad mineralization in these binturongs is consistent with hydroxyapatite deposition disease, which is rarely described in humans and animals as a primary familial condition or a secondary condition often associated with renal injury.
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Felid semen has historically been frozen using an egg yolk-based cryopreservation medium (TEY). However, the use of egg introduces several potential concerns, such as variability in composition, microbial contamination, and regulatory... more
Felid semen has historically been frozen using an egg yolk-based cryopreservation medium (TEY). However, the use of egg introduces several potential concerns, such as variability in composition, microbial contamination, and regulatory issues. Our recent research has focused on developing an animal protein-free medium containing soy lecithin (SOY). Our studies revealed that SOY was superior to TEY for freezing domestic cat sperm and provided similar results for freezing ocelot, Pallas’ cat, and fishing cat sperm. The objective of this study was to compare SOY to the standard TEY for sperm cryopreservation in 2 wild cat species: the black-footed cat and sand cat. Semen was collected from adult male cats (n=6/species) via electroejaculation, split into 2 aliquots, centrifuged, resuspended in either SOY or TEY, slow-cooled, and frozen in straws over nitrogen vapor. Sperm motility [percent progressively motile (PPM); rate of progressive motility on 0-5 scale (RPM)] was evaluated at 0, 1,...
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Servals and Canada lynx are managed by species survival plans in North American zoos, but current populations are not sustainable. Increased knowledge of their reproductive biology would benefit breeding management and development of... more
Servals and Canada lynx are managed by species survival plans in North American zoos, but current populations are not sustainable. Increased knowledge of their reproductive biology would benefit breeding management and development of assisted reproductive techniques. The aims of our study were to (1) evaluate effectiveness of urethral catheterization and electroejaculation (EEJ) for semen collection; (2) characterise basal seminal traits; and (3) compare effectiveness of semen cryopreservation methods. Semen was collected from 6 servals and 9 Canada lynx via a urinary catheter (3.5 Fr×22 cm, inserted 15cm into the urethra), followed by EEJ under dexmedetomidine-ketamine anaesthesia. To assess the effect of seasonality on lynx seminal traits, semen was collected before (late January), during (mid-February to mid-March), and after (early April) the peak breeding season. Serval and lynx semen were frozen by conventional slow freezing (i.e. in 0.25-mL straws cooled to 4°C for 2h and fro...
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Research Interests:
Wild bull Asian elephants spend time in all-male groups. Therefore, managers of ex situ populations increasingly house bulls together. We examined the social interactions of five bull Asian elephants at Denver Zoo, using instantaneous... more
Wild bull Asian elephants spend time in all-male groups. Therefore, managers of ex situ populations increasingly house bulls together. We examined the social interactions of five bull Asian elephants at Denver Zoo, using instantaneous sampling to compare social interactions across adolescent and mature bulls, and bulls with a social history prior to the integration of this group compared to bulls with no social history. Both age and social history significantly affected bull behavior. Adolescent bulls exhibited more affiliative and submissive behaviors when housed with mixed-age and mature social partners compared to with only adolescents, and less non-contact agonistic behavior and less time in proximity to a conspecific with mixed-age groups compared to with only other adolescents. Mature bulls exhibited more affiliative behavior when they were with only adolescent bulls compared to only mature bulls, and more time in proximity to a conspecific and increased contact agonistic beha...
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Historically, semen banking in felids has required sample collection via electroejaculation followed by sperm freezing in straws over LN2 vapor. Recent modifications include urethral catheterization of males treated with α-2 agonists for... more
Historically, semen banking in felids has required sample collection via electroejaculation followed by sperm freezing in straws over LN2 vapor. Recent modifications include urethral catheterization of males treated with α-2 agonists for semen recovery and vitrification of cat sperm by suspension in a sucrose-based cryomedium and direct pelleting into LN2. In combination, these latter methods greatly simplify semen cryopreservation in cats but protocols need to be optimized for applied usage. In the present study, our goal was to assess the effect of 2 variables—pellet volume and thawing temperature—on post-thaw sperm motility, acrosome status, and in vitro fertility. Semen was collected from 3 males (3 ejaculates/male) via urethral catheterization under dexmedetomidine-ketamine anaesthesia. Sperm were diluted in Feline Optimized Culture Medium (FOCM), centrifuged (8 min; 300 × g), and resuspended in a soy-lecithin-based vitrification medium (with 0.2 M sucrose). After a 5-min equil...
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Zoological institutions aim to continually improve the lives of the animals under their stewardship. To this end, bull elephants are now increasingly maintained in all-male groups to mimic social conditions observed in the wild. While... more
Zoological institutions aim to continually improve the lives of the animals under their stewardship. To this end, bull elephants are now increasingly maintained in all-male groups to mimic social conditions observed in the wild. While cortisol is the most frequently used “stress” biomarker, secretory immunoglobulin A (sIgA) as a measure of health and positive affect, and the social hormone, oxytocin, are increasingly viewed as additional markers of welfare. The introduction of a pair of bull elephants to an existing group of three bull elephants at Denver Zoo presented an opportunity to assess sIgA, oxytocin and cortisol in response to the socialization process. In this study, sIgA varied greatly between individuals and did not correlate with cortisol but did correlate with salivary oxytocin. sIgA and oxytocin concentrations differed the most between social and solo situations during the introduction period compared to before bulls were introduced, and after a stable group had been ...
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Wild bull Asian elephants spend time in all-male groups. Therefore, managers of ex situ populations increasingly house bulls together. We examined the social interactions of five bull Asian elephants at Denver Zoo, using instantaneous... more
Wild bull Asian elephants spend time in all-male groups. Therefore, managers of ex situ populations increasingly house bulls together. We examined the social interactions of five bull Asian elephants at Denver Zoo, using instantaneous sampling to compare social interactions across
adolescent and mature bulls, and bulls with a social history prior to the integration of this group compared to bulls with no social history. Both age and social history significantly affected bull behavior. Adolescent bulls exhibited more affiliative and submissive behaviors when housed with
mixed-age and mature social partners compared to with only adolescents, and less non-contact agonistic behavior and less time in proximity to a conspecific with mixed-age groups compared to with only other adolescents. Mature bulls exhibited more affiliative behavior when they were with only adolescent bulls compared to only mature bulls, and more time in proximity to a conspecific and increased contact agonistic behavior with at least one adolescent compared to only mature bulls.
Bulls in new social groups engaged in more affiliative, agonistic, and submissive behaviors, and spent less time in proximity, than when they were in previously established social combinations. As more institutions house bulls socially, our results provide insights into factors that may affect bull social interactions.
adolescent and mature bulls, and bulls with a social history prior to the integration of this group compared to bulls with no social history. Both age and social history significantly affected bull behavior. Adolescent bulls exhibited more affiliative and submissive behaviors when housed with
mixed-age and mature social partners compared to with only adolescents, and less non-contact agonistic behavior and less time in proximity to a conspecific with mixed-age groups compared to with only other adolescents. Mature bulls exhibited more affiliative behavior when they were with only adolescent bulls compared to only mature bulls, and more time in proximity to a conspecific and increased contact agonistic behavior with at least one adolescent compared to only mature bulls.
Bulls in new social groups engaged in more affiliative, agonistic, and submissive behaviors, and spent less time in proximity, than when they were in previously established social combinations. As more institutions house bulls socially, our results provide insights into factors that may affect bull social interactions.
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High numbers of ovarian adenocarcinomas have been documented in captive jaguars, which are rare in other felids.1,4 Formalin fixed, paraffin embedded tissues from 55 captive, female jaguars between 1988-2014 were collected. Twenty-three... more
High numbers of ovarian adenocarcinomas have been documented in captive jaguars, which are rare in other felids.1,4 Formalin fixed, paraffin embedded tissues from 55 captive, female jaguars between 1988-2014 were collected. Twenty-three jaguars (40%) had ovarian carcinoma (five with bilateral tumors), 14 had mammary carcinoma, and of these, five had both ovarian and mammary carcinoma. No association has been found between ovarian cancer and the use of exogenous progestins in zoo felids, and in these cases, only nine of 23 animals with ovarian adenocarcinoma had a history of exogenous progestin exposure.2,5 An inherited germline mutation is suspected, and candidate genes include those involved in the carcinogenesis of human ovarian and breast cancer, such as BRCA1 and BRCA2.3 These tumors most often occur in middle-aged, post-reproductive jaguars, though a homozygous germline mutation in BRCA1 could lead to embryonic lethality, impairing captive breeding. To further investigate the role of BRCA1 in tumorigenesis, jaguar genomic DNA was first extracted from whole blood. Primers were designed using the domestic cat BRCA1 genomic DNA sequence. Jaguar and domestic cat genomic DNA was amplified using
PCR and Sanger sequencing. Multiple variations in the jaguar BRCA1 sequence were detected, including five nonsynonymous point mutations and one three base pair insertion. Any association between these sequence variations and tumor development or phenotype, as well as other candidate genes are being investigated. Knowledge of risk factors for the development of ovarian carcinoma in jaguars will assist with the medical management and breeding recommendations of this endangered species in captivity.
PCR and Sanger sequencing. Multiple variations in the jaguar BRCA1 sequence were detected, including five nonsynonymous point mutations and one three base pair insertion. Any association between these sequence variations and tumor development or phenotype, as well as other candidate genes are being investigated. Knowledge of risk factors for the development of ovarian carcinoma in jaguars will assist with the medical management and breeding recommendations of this endangered species in captivity.
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Reproductive tumors can impact conception, pregnancy, and birth in mammals. These impacts are well documented in humans, while data in other mammals are limited. An urgent need exists to understand the reproductive impact of these lesions... more
Reproductive tumors can impact conception, pregnancy, and birth in mammals. These impacts are well documented in humans, while data in other mammals are limited. An urgent need exists to understand the reproductive impact of these lesions in endangered species, because some endangered species have a documented high prevalence of reproductive tumors. This article documents that the prevalence of both benign and malignant neoplasia differs between African and Asian elephants, with Asian elephants more frequently diagnosed and negatively affected by both. The prevalence of these tumors across mammalian species is compared, and impact plus treatment options in human medicine are reviewed to inform decision making in elephants. Evidence suggests that reproductive tumors can negatively impact elephant conservation. Future studies that document reproductive outcomes, including the success of various treatment approaches in elephants with tumors will benefit conservation efforts.
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Giraffe present unique contraception challenges as males persistently pursue females during estrus. Year-round pursuit during frequent recurring estrus can pose significant risk under slippery conditions. Complete ovarian suppression is a... more
Giraffe present unique contraception challenges as males persistently pursue females during estrus. Year-round pursuit during frequent recurring estrus can pose significant risk under slippery conditions. Complete ovarian suppression is a useful tool in giraffe because it eliminates estrous behavior, interest from the male, and controls reproduction. Effective reproduction control in giraffes has been achieved with porcine zona pellucida, oral melengestrol acetate, and depot medroxy-progesterone acetate. However, these methods allow some degree of folliculogenesis and estrous behavior. Improvest® is a gonadotropin releasing hormone (GnRH) immunological product that elicits antibodies against GnRH and abrogates the effects of endogenous GnRH. This study evaluated the efficacy of Improvest® for gonadal suppression in seven females and one male giraffe by monitoring steroid hormones. Seven female giraffe were treated intramuscularly with an initial dose, a booster at 4 weeks and maintenance boosters at 3-month intervals (600 µg/dose) for 12 months. Six females were on supplemental contraception during the induction phase because separation from males was not possible. In the male (treated with 400 µg), testosterone concentrations decreased after the second injection. However, even with low serum testosterone concentrations, mounting (of nontreated females) behavior was still observed occasionally. Ovarian activity was suppressed in all treated females and interest by the males stopped; supplemental contraceptives (during the induction phase) did not impede the effect of Improvest®. After 15.3 months (seven doses), Improvest® was discontinued in three females which no longer needed contraception. In these females, ovarian activity was noted approximately 90 days after the last dose.
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There is a growing need for animal care institutions to house multiple bull elephants as the population increases due to transfers from private ownership and the births of male offspring in managed care. Elephants in North American,... more
There is a growing need for animal care institutions to house multiple bull elephants as the population increases due to transfers from private ownership and the births of male offspring in managed care. Elephants in North American, European, and Latin American zoos exhibit stereotypies—repetitive, fixed behaviors. Previous research demonstrated that housing Asian elephants alone increased stereotypic behavior. Therefore, for animals in managed care, social restriction can contribute to stereotypy and, by extension, reduce welfare. In this study, we examine how being alone affects stereotypic behavior by monitoring pacing and head-bobbing in individual bull Asian elephants at Denver Zoo when housed alone as well as with other bulls. Two young males arrived at Denver Zoo in September 2018 and joined an existing all-male group of three elephants that were previously socialized and housed together. From July 2018 to December 2019, we used instantaneous scan sampling to collect data on ...
Abstract: In zoos, rock hyrax (Procavia capensis) are commonly maintained in groups and population control is necessary. Here we report on hydrometra prevalence in a group of rock hyraxes. Prevalence of hydrometra in this small group... more
Abstract: In zoos, rock hyrax (Procavia capensis) are commonly maintained in groups and population control is necessary. Here we report on hydrometra prevalence in a group of rock hyraxes. Prevalence of hydrometra in this small group (4/8) far exceeds reproductive pathology prevalence previously reported for this species under managed care. Affected females were nulliparous, but had not been contracepted; instead they were maintained as a single-sex group. The first case presented as sudden death and three additional cases were diagnosed antemortem via ultrasound. Two of these underwent ovariohysterectomy to treat the severe hydrometra. The last case was a mild hydrometra and during follow-up exam was found to have spontaneously resolved. Detailed information regarding clinical presentation, diagnostics and surgical techniques are provided.
Male associations are a typical component of elephant society, allowing bulls to practice appropriate social behavior. To improve zoo elephant welfare, it is important to provide bulls with social opportunities. In fall 2018, Denver Zoo... more
Male associations are a typical component of elephant society, allowing bulls to practice appropriate social behavior. To improve zoo elephant welfare, it is important to provide bulls with social opportunities. In fall 2018, Denver Zoo added two bull Asian elephants to its existing all-male group of three bulls, offering the opportunity to conduct a systematic behavioral study of the integration of the new bulls into the resident group. We recorded aggressive and affiliative behaviors before, during, and after the introduction of the new males. The proportion of aggressive behavior was significantly higher during the five-month introduction period compared to before their introduction. By the end of the study period, the elephants engaged in significantly more affiliative behavior and less aggressive behavior than during the introduction period, suggesting they had formed a new stable social dynamic. These results suggest group compatibility and positive elephant welfare resulting from housing male elephants together and can be used to inform management plans for bull elephants that prioritize their welfare.
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As evidenced by numerous case reports from zoos, neoplasia in felids is common, but most reports are limited to Panthera species in North America or Europe. In order to obtain a wider epidemiologic understanding of neoplasia distribution,... more
As evidenced by numerous case reports from zoos, neoplasia in felids is common, but most reports are limited to Panthera species in North America or Europe. In order to obtain a wider epidemiologic understanding of neoplasia distribution, necropsy records at seven facilities (USA, Mexico, Colombia, Peru, and Brazil) were evaluated. In contrast to others, this study population (195 cases, 16 species), included many non-Panthera felids. Overall neoplasia prevalence was 28.2% (55/195). Panthera species had a higher prevalence of neoplasia than non-Panthera species (52.5%; vs. 13.0%). Lions (66.7%), jaguars (55.0%), and tigers (31.3%) had the highest species-specific prevalence of neoplasia. Neoplasms in Panthera species were more frequently malignant than in non-Panthera (86.1% vs. 55.6%). The systems most commonly affected were the reproductive, hematolymphoid, and respiratory. The range of management conditions and more varied genetic backgrounds support a robust taxonomic pattern an...
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Simple Summary Since the advent of microbiome research, this field has seen an explosion of both techniques and subfields. Researchers have aimed not only to classify microbiome membership and diversity among varying hosts, but to also... more
Simple Summary Since the advent of microbiome research, this field has seen an explosion of both techniques and subfields. Researchers have aimed not only to classify microbiome membership and diversity among varying hosts, but to also identify and understand new and novel microbial lineages. This wealth of knowledge continues to grow, and with it the potential to use microbiome databases as diagnostic tools. This diagnostic application is of great importance and interest in zoological settings, as it may provide a non-invasive assessment of animal health. However, before this tool can be utilized in zoos, more data are needed to assess the extent of microbial variation characteristics to each host species to know what may be problematic versus normal. The aim of this research was to characterize variation of the microbiome at the individual level within managed populations of western lowland gorillas in three zoological institutions. Abstract The last few decades have seen an outpo...
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Abstract. Mammary cancer occurs among all taxonomic groups, and comparing the disease in animals with breast cancer in women could greatly improve our understanding of the relevant risk factors and genetic profiles for this disease.... more
Abstract. Mammary cancer occurs among all taxonomic groups, and comparing the disease in animals with breast cancer in women could greatly improve our understanding of the relevant risk factors and genetic profiles for this disease. Differences in cancer prevalence between carnivores and herbivores and between captive and wild carnivores are striking and support the hypotheses that diet and reproductive history are major risk factors. Domestic dogs and cats have a high prevalence of mammary tumors, and the majority of tumors in cats are aggressive cancers. Many domestic dogs and cats are prevented from breeding, resulting in their being exposed to recurrent estrogen peaks followed by high persistent levels of progesterone. Therefore progesterone appears to be a significant risk factor for cancer development. Supporting this suspicion is the observation that most mammary cancers in zoo cats are in those treated with the potent synthetic progestin contraceptive, melengestrol acetate. ...
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Jaguars are an endangered species and represent the only felid in the Americas from the genus Panthera. Wild jaguars continue to be threatened by habitat loss and other human impacts; therefore, maintaining a healthy breeding population... more
Jaguars are an endangered species and represent the only felid in the Americas from the genus Panthera. Wild jaguars continue to be threatened by habitat loss and other human impacts; therefore, maintaining a healthy breeding population in zoological institutions is critical to jaguar survival. Ovarian adenocarcinoma (OC) commonly occurs in adult jaguars housed in North American zoological institutions, and is an important cause of mortality in this population. This neoplasm is very rare in domestic cats and has not been reported in other zoo felids. Archived, formalin-fixed, paraffin embedded (FFPE) reproductive tissues from 55 female jaguars were examined. OC was confirmed histologically in 22 (40%) jaguars originating from 17 zoological institutions. Seven jaguars with OC were traced back to one breeding pair, and pedigree analysis shows an autosomal dominant pattern of inheritance. The purpose of this study is to investigate the genetic pathogenesis of ovarian adenocarcinoma in jaguars by identifying an inherited germline mutation in BRCA1, BRCA2 or other cancer genes with known involvement in human ovarian and breast cancer. A candidate gene approach was used for investigation, as minimal wild type gene sequences are available for the jaguar, and no previous studies have been undertaken to investigate genetic mechanisms of disease in this species. By utilizing genomic information available from closely related species, a targeted library preparation and next-generation sequencing approach was used to evaluate exon sequences of multiple cancer genes (n=276) in paired OC and normal FFPE tissues from each jaguar. Probes designed in this assay captured the majority of target regions, covering 92% of total base pairs within the 1.4 Mbp target region. Average depth across FFPE samples was 114x. Multiple variants were detected in jaguar candidate genes. One variant of interest in BRCA2 exon 11 includes a single nucleotide variant in the jaguar sequence that corresponds to position c.3732 in humans. The c.3732C>G variant gives rise to the substitution p.Ser1252Arg which is predicted to be potentially deleterious. This variant was present in all jaguar samples, but demonstrates loss of heterozygosity in the jaguar ovarian adenocarcinomas compared to paired normal tissues. This variant is in the region of exon 11 containing several amino acid (BRC) repeats essential for RAD51 binding. Maintaining genetic diversity in endangered animals, such as the jaguar, while preserving the species in zoological institutions by captive breeding is an important aspect of their conservation. Identifying a germline mutation associated with OC in jaguars will enable the identification of mutation carriers and will allow for educated breeding decisions, better disease monitoring, and earlier intervention. Jaguars may also be a naturally-occurring animal model that parallels hereditary breast and ovarian cancer syndrome in humans. Citation Format: Sarah Corner, DVM, MS, Dipl ACVP, Maciej Parys, DVM, PhD, Anneke Moresco, DVM, PhD, Vilma Yuzbasiyan-Gurkan, PhD, and Dalen Agnew, DVM, PhD, Dipl ACVP. OVARIAN ADENOCARCINOMA IN JAGUARS (PANTHERA ONCA): A NATURALLY-OCCURRING MODEL OF HUMAN INHERITED OVARIAN CANCER? [abstract]. In: Proceedings of the 11th Biennial Ovarian Cancer Research Symposium; Sep 12-13, 2016; Seattle, WA. Philadelphia (PA): AACR; Clin Cancer Res 2017;23(11 Suppl):Abstract nr TMEM-020.
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This multi-institutional collaborative study of neoplasia in snakes reviewed medical records of snakes at each facility to determine species prevalence, survival, and methods of treatment. Complete species numbers of snakes were also... more
This multi-institutional collaborative study of neoplasia in snakes reviewed medical records of snakes at each facility to determine species prevalence, survival, and methods of treatment. Complete species numbers of snakes were also collected at each facility. In total, 65 species, 133 snakes, and 149 unique neoplasias were included in this study. Affected species, age, sex, and their tumor prevalence, tumor type and location, metastasis, treatment, and survival data are reported. The highest species-specific tumor prevalence was in Common or Northern Watersnakes (Nerodia sipedon) (30.8%, n = 4 of 13), Eastern Diamond-Backed Rattlesnakes (Crotalus adamanteus) (26.3%, n = 5 of 19), and Timber rattlesnakes (Crotalus horridus) (22.7%, n = 5 of 22). Malignant tumors predominated (86.6%, n = 129 of 149) with soft tissue sarcomas being the most common (30.2%, n = 45 of 149). Snakes with malignant neoplasia, metastases, or indeterminate presence of metastases were statistically more likel...
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In a collection of 6 young binturongs ( Arctictis binturong), 3 presented with anorexia, lethargy, and footpad swelling diagnosed by surgical biopsy as calcinosis circumscripta. Despite supportive care over the next 4 years, affected... more
In a collection of 6 young binturongs ( Arctictis binturong), 3 presented with anorexia, lethargy, and footpad swelling diagnosed by surgical biopsy as calcinosis circumscripta. Despite supportive care over the next 4 years, affected binturongs had progressive weight loss, hyperphosphatemia, and hyperkalemia and developed large radiodense deposits in tissues adjacent to appendicular joints, thoracolumbar vertebrae, and the sternum. Two binturongs died and necropsies showed severe periarticular mineral deposition with fibrosis and granulomatous inflammation. Additionally, binturongs had mineralization of distal renal tubules, mineralization of the renal interstitium, and marked mineralization of the pulmonary interstitium and peribronchiolar smooth muscle. Foot biopsies from the surviving binturong were evaluated by spectroscopic microanalysis and were positive for hydroxyapatite, Ca10(PO4)6(OH)2. Periarticular and footpad mineralization in these binturongs is consistent with hydroxy...
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This study aimed to evaluate normal features of the heart and lower respiratory tract in toco toucans by means of radiography and helical computed tomography (CT) scanner. Fifteen healthy adult toco toucans (Ramphastos toco), 10 females... more
This study aimed to evaluate normal features of the heart and lower respiratory tract in toco toucans by means of radiography and helical computed tomography (CT) scanner. Fifteen healthy adult toco toucans (Ramphastos toco), 10 females and 5 males, average body mass of 650 g were studied. CT examination as well as right lateral and ventrodorsal radiographic examinations of the coelomic cavity were performed under chemical restraint. Heart, lungs, air sacs, trachea and syrinx were analysed. The mean values of heart length, heart width and thoracic cavity in radiographs were, respectively, 23.76 mm, 25.94 mm and 48.87 mm. In both X‐rays and CT scans, the lung parenchyma had honeycomb‐like pattern. The topographic areas of the anterior and posterior air sacs were visualized as dark and air‐filled spaces in X‐rays. On CT evaluation, the air sacs occupied a larger area in the coelomic cavity compared to X‐ray. In the lateral radiographic view, the cervical part of the trachea was positioned more ventrally in the transition from cervical to thoracic regions showing a V‐shaped appearance. In all CT planes was visible division of the trachea into the right and left main bronchi at the level of 3rd thoracic vertebra. The syrinx was difficult to visualize in X‐rays, but on CT it was easily identified in axial slice. In conclusion, the normal features of toco toucan's heart and lower respiratory tract that were determined on X‐rays and CT scans are useful to compare with sick toco toucans, as well as other bird species.
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ABSTRACT A 2-year-old female African pygmy hedgehog (Atelerix albiventris) presented to emergency for anorexia, lethargy and vulvar discharge. Tranquilization with midazolam, administration of oxygen therapy and facemask anesthesia with... more
ABSTRACT A 2-year-old female African pygmy hedgehog (Atelerix albiventris) presented to emergency for anorexia, lethargy and vulvar discharge. Tranquilization with midazolam, administration of oxygen therapy and facemask anesthesia with isoflurane were used for radiography study which showed increased radio-opacity and silhouette sign in the thoracic cavity. The patient underwent cardio-respiratory arrest during the performance of TFAST echocardiography. TFAST confirmed pleural effusion, a nodule in the chamber of the right atrium. Abdominal ultrasound revealed two fluid filled structures compatible with left ovarian cysts. Necropsy confirmed dilated cardiomyopathy, bilateral atrial thrombi, endometrial hyperplasia and two left ovarian cysts.